This application claims the benefit of a Japanese Patent Application No. 2003-017468 filed Jan. 27, 2003, in the Japanese Patent Office, the disclosure of which is hereby incorporated by reference.
1. Field of the Invention
The present invention generally relates to yield percentage managing methods and apparatuses and computer-readable storage media, and more particularly to a yield percentage managing method and a yield percentage managing apparatus for automatically managing a yield percentage which indicates an amount of processed (or manufactured) products (or goods) that can be processed or manufactured from raw materials, and to a computer-readable storage medium which stores a computer program for causing a computer to manage the yield percentage.
In retail business and the like, raw materials are bought and processed so as to produce processed products, and the processed products are sold. Examples of such processed products are fishery products such as fishcakes (or so-called surimi products), and livestock products such as bacon and ham. When producing the processed products from the raw materials, there are portions of the raw materials that can be used and portions which cannot be used for the processed products. For example, if the raw material is a fish, the meat can be used to produce the fishcake, but the skin, bone and other portions of the fish cannot be used for the fishcake. In addition, when producing a package of raw fish slices, that is, the so-called sashimi slices, some portions of the meat cannot be used for the raw fish slices and are wasted depending on how the fish is cut.
In this specification, the “yield percentage” refers to a percentage of the raw material that is usable to produce the processed products, and is dependent on the portions of the raw material, the manner in which the raw material is cut and the like. In addition, the “processed products” refer to the products (goods, merchandises and the like) that are produced by processing the raw materials. Furthermore, the “processing” of the raw material includes subjecting the raw material to a process such as heating (baking, frying, steaming and the like), cutting and the like.
2. Description of the Related Art
The yield percentage is used to manage the purchasing budget, the ordering of the stock, the cost of the processed products and the like. By use of the yield percentage, it is possible, for example, to know the amounts of raw materials to be ordered by converting the target processed products to be sold to the raw materials. Accordingly, if an accurate yield percentage can be managed, it is possible to improve the accuracy of ordering the raw materials. In addition, it is possible to prevent ordering an excessive amount of raw material, which would otherwise cause a loss by having to destroy the excessive raw material or, cause unnecessary expenses to maintain the stock of the excessive raw material. Moreover, it is possible to prevent ordering too little amount of raw material, which would otherwise cause the processed products to be sold out and miss the opportunity of selling the processed products.
The yield percentage also changes depending on the individual worker or the number of workers who process the raw materials to produce the processed products. For this reason, in order to optimize management of the purchasing budget, the ordering of the stock, the cost of the processed products and the like, it is desirable to carry out the management so that the yield percentage is constantly corrected or updated to suit the situation.
FIG. 1 is a diagram for explaining a conventional method of managing the yield percentage. Conventionally, in order to manage the yield percentage, it was necessary to obtain the information shown in FIG. 1, for example. In FIG. 1, the left ordinate indicates the amount of material in arbitrary units, the right ordinate indicates the amount of sold items, and the abscissa indicates the selling time in arbitrary units. The material corresponds to the raw material, and the items correspond to the processed products. The amount of material may be the number of materials or, the weight of the material. For the sake of convenience, it is assumed that one kind of item is produced from one kind of target material.
In FIG. 1, M denotes an amount of initial stock of the target material, N denotes a buying amount of the target material, L denotes an amount of final stock of the target material, P denotes an amount of the target material used during the present term, p1 denotes an amount of sold target items, p2 denotes an amount of destroyed target items, p3 denotes an amount of present stock of the target item (an amount of unsold target items which can be sold), p4 denotes an amount of initial stock of the target material which is obtained as a result of a previous stocktaking of the target items, and p5 denotes an amount of stock of the target material which is obtained as a result of a stocktaking of the target items made during the present term. The amount M of initial stock of the target material is obtained as a result of a previous stocktaking of the target material. The buying amount N of the target material is the amount of the bought target material which is allocated when the buying of the target material becomes definite. The amount L of final stock of the target material is the amount of the target material which is presently in stock as a result of the stocktaking of the target material. The amount P of the target material used during the present term is the amount of the target material which is actually used to produce the target items, of the amount M+N, and includes the amount of the target material which is not used for the target items but is destroyed.
For example, the yield percentage of the target item with respect to the target material is managed in the following manner. First, the amount of the target material used during the present term, P, is obtained from the following formula (1).P=M+N−L  (1)Then, a theoretical value Q of the amount of the target material used during the present term is obtained from the following formula (2), using a yield percentage Yr of the target item which is registered in advance.
                                                        Q              =                                                (                                      p1                    +                    p2                    +                    p3                    -                    p4                                    )                                /                Yr                                                                                        =                                                (                                      p1                    +                    p2                    +                    p5                                    )                                /                Yr                                                                        (        2        )            
Next, the amount P and the theoretical value Q are compared, and the registered yield percentage Yr is corrected or updated depending on an error which is obtained as a result of the comparison. Conventionally, the operations of obtaining the amount P and the theoretical value Q, comparing the amount P and the theoretical value Q, and correcting or updating the registered yield percentage Yr depending on the error obtained from the compared result, are basically made manually by an operator.
For example, a Japanese Laid-Open Patent Application No. 5-73573 proposes a conventional method of managing the yield percentage.
But conventionally, the yield percentage of the target processed products (items) with respect to the target raw material (material) is basically managed by a manual operation of the operator. For this reason, there were problems in that the operator must perform a troublesome operation and that it takes time to perform the troublesome operation.
In addition, in order to manage the yield percentage, it is necessary to use the amount M of initial stock of the target material, the buying amount N of the target material, and the amount L of final stock of the target material, in order to obtain the amount P of the target material used during the present term. Furthermore, it is also necessary to use the registered yield percentage Yr, the amount p1 of sold target items, the amount p2 of destroyed target items, and the amount p5 of stock of the target material which is obtained as a result of a stocktaking of the target items made during the present term (or the amount p3 of present stock of the target item and the amount p4 of initial stock of the target material which is obtained as a result of a previous stocktaking of the target items), in order to obtain the theoretical value Q of the amount of the target material used during the present term. Therefore, it was necessary to accurately manage the information M, N, L, p1, p2 and p5 (or p3 and p4). In general, the information M, N and L related to the material can be managed in relatively accurate and simple manner. However, in general, there was a problem in that a troublesome and time-consuming operation is required in order to accurately manage the information p1, p2 and p5 (or p3 and p4) related to the item.
On the other hand, if the information p1, p2 and p5 (or p3 and p4) related to the item is not accurately managed, the management of the yield percentage would have to rely on the operator's experience and perception. As a result, an accurate yield percentage cannot be obtained unless the operator is skilled, and the yield percentages obtained by different operators may differ greatly. Accordingly, there was a problem in that it is difficult to appropriately manage the yield percentage.
Moreover, when the operator corrects or updates the registered yield percentage Yr by obtaining the yield percentage, the correction or updating relies on the operator's experience and perception. Consequently, there was a problem in that it is impossible to appropriately correct or update the yield percentage unless the operator is skilled.